Nomenclature

IUPAC - International Union of Pure and Applied Chemistry, which provides recommendations on many aspects of nomenclature.

Nomenclature is a key tool for effective communication in the chemical sciences. There are 3 types of chemical nomenclature

1. Nomenclature of Organic chemistry - Blue book
2. Nomenclature of Inorganic chemistry - Red book
3. Nomenclature of Polymer chemistry - Purple book

Substitutive Nomenclature

It is the main method for organic-chemical compounds. It is used mainly for compounds of carbon and elements of groups 13 - 17.

For naming purposes, a chemical compound is treated as

• a combination of a parent compound and characteristic (functional) groups, one of which is designated the principal characteristic group
• A systematic name is based on the name of most senior parent compound in which the substitution of hydrogen atoms is represented by a SUFFIX for the principal characteristic group(s).
• PREFIXes representing less senior characteristic groups and other substituent groups, and locants that specify their locations.

Components of systematic substitutive names

1. Locants - to indicate the position of substituents or other structural features.
2. Enclosing mark, in the nesting order {[( )]} - to indicate which parts of a name belong together
3. Multiplicative prefixes. Ex. trichloro...

(4S,5E)-4,6-dichlorohept-5-en-2-one

• hept(a) - parent (heptane)
• en(e) - unsaturation ending
• di - multiplicative prefix
• 2, 4, 5, 6 - locants
• one - suffix of principal characteristic group
• chloro - substituent prefix
• E S - stereodescriptors
• ( ) - enclosing marks

Creation of systematic names

The following order is used for the formation of systematic name

1. Determine the principal characteristic group to be cited as the SUFFIX.
2. Determine the senior parent amongst those structural components attached to a principal characteristic group.
3. Name the parent hydride and specify any unsaturation.
4. Combine the name of the parent hydride with the suffix for the principal characteristic group.
5. Identify the substituents and arrange the corresponding prefixes in alphabetical order.
6. Insert multiplicative prefixes, without changing the already established order, and insert locants.
7. Determine the chirality centres and other stereogenic units, such as double bonds, and add stereodescriptors.

Reference

Brief guide to the nomenclature of organic chemistry, Pure Appl. Chem., 2020, 92 (3), 527 - 539.